Our invention relates to apparatus for performing orthopedic surgery and particularly for apparatus used in preparing bones of patients to receive prosthetic devices. In particular, our invention relates to a drill guide and template having a universal joint interposed between a handle and the template. The universal joint can be locked, providing great flexibility combined with stability. We have found our invention particularly useful for preparing the glenoid cavity of a shoulder, where access may be particularly constrained, but our invention is applicable to orthopedic procedures generally.
Orthopedic implants which replace diseased or broken joints are well-known. In recent years, however, implants have become increasingly complex and precise. Surgeons strive for accurate, replicable surgical techniques so that precise fits can be obtained. Increased contact between bone and prostheses has been found to increase long-term fixation. Jigs and guides can be used by surgeons for preparing the bone to receive prosthetic implants. Use of these guides may be constrained, however, by the surrounding soft tissue, muscles, and tendons of the patient, and by the technique of the particular surgeon. These limitations apply to all joint replacements, but they particularly relevant for shoulder replacements because the available operating room may be particularly restricted. An example of a glenoid prosthesis and surgical technique is described in U.S. Pat. No. 4,964,865 to Burkhead, et al., which patent is assigned to the assignee of our invention. To install the device described by Burkhead, a surgeon would resect a flat surface within the glenoid cavity against which a flat medial surface of the glenoid prosthesis would rest. The surgeon must also drill accurate holes for pegs. If the prosthesis is accurately mounted on the bone, the prosthesis will not rock against the bone and the joint would be less likely to fail. The surgeon should therefore, accurately prepare the glenoid surface to receive the prosthesis.
To prepare the surface, drill guides and templates have been used. In the past, however, these drill guides have generally been mounted with fixed handles. A fixed handle provides stability for the drill guide, but the drill guide cannot be easily adapted to the particular patient or the style of the attending surgeon. Examples of such drill guides available to surgeons are those produced by Biomet for their Biomodular(.TM.) Total Shoulder and Biangular (.TM.) Shoulder or by Richards Medical Company for their Cofield(.TM.) Total Shoulder System.
It is an object of our invention, therefore, to provide a drill guide for use in orthopedic surgery which can adapt to patient anatomy and surgical technique.
It is also an object of our invention to provide a drill guide which can be both adaptable and stable.
Another object of our invention is to provide a surgical drill guide with a handle which can be swiveled to a desired position and locked in position.